<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<title>程序计数器</title>
	</head>
	<body>
		<div id='app'>
			<h2>当前计数：{{counter}}</h2>
			<button @click="add">+</button>
			<button @click="sub">-</button>
		</div>
		<script src="js/vue.js" type="text/javascript" charset="utf-8"></script>
		<script type="text/javascript">
			const app = new Vue({
				el:'#app',
				data :{
					counter: 0
				},
				methods:{
					add: function(){
						console.log("add被执行")
						this.counter++
					},
					sub: function(){
						console.log("sub被执行")
						this.counter--
					}
				},
				beforeCreate:function(){
					console.log('beforeCreated')
				}
				created:function(){
					console.log('created')
				},
				mounted:function(){
				    console.log('mounted')
				}
			})		
		</script>		
	</body>
</html>
